1. Field of the Invention
The present invention relates to a method of inputting a name and, more particularly, to a method of inputting one of predetermined names through a key pad input image.
2. Description of the Related Art
In a navigation apparatus provided in a motor vehicle or the like to perform vehicle travel guidance to a selected destination, the current position of the vehicle is detected and map data about places around the vehicle position is read out from a map storage medium (e.g., a compact disc read only memory (CD-ROM) or a digital versatile disc (DVD)) to display a map on a display screen with a vehicle position mark superposed on the corresponding portion of the map. As the vehicle travels and the current position changes, the vehicle position mark on the screen is moved or the map is scrolled while the vehicle position mark is fixed at a predetermined position, e.g., at a center of the screen, thereby enabling a driver to have map information at a glance about places around the vehicle position.
Such an on-vehicle navigation apparatus has a function of inputting a name of a place or a point formed of letters of, for example, the Japanese or English language presented in the order of the kana syllabary or in alphabetical order, and displaying a map containing the point corresponding to the input name. To input a point name, a key pad input image (letter pallet) formed of kana letters or alphabetical letters is displayed on a monitor screen in the order of the kana syllabary or in alphabetical order, and necessary letters are successively designated in the displayed letters to be input.
The function of displaying a map showing places around a selected point by only inputting a name of the point based on this place input method is convenient. However, in the process of inputting a point name from the letters in the order of the kana syllabary or in alphabetical order, it is necessary to search out each of letter keys (kana or alphabet keys) corresponding to the point name and to input the letters one by one. Thus, troublesome inputting operations are required and there is a considerable possibility of an input error.
An object of the present invention is to provide a method which enables a point name to be input by a simple operation while reducing the necessary memory capacity.
To achieve this object, according to one aspect of the present invention, there is provided a method of inputting one of predetermined names through a key pad input image, the method including the steps of (1) preparing a name list in which a plurality of names formed of alphabetical letters, kana letters, or like characters are registered in alphabetical order or in the order of the kana syllabary, and a table formed by storing sequences of n leading characters and data related to each sequence of n leading characters, the data representing information as to whether some of the registered names in the name list have the corresponding sequence of n leading characters, (2) making, when one of the sequences of n leading characters is input, an examination as to whether some of the registered names in the name list have the same sequence of characters as the input sequence of n characters by referring to the table, (3) searching, according to an affirmative result of the examination step, the name list for some of the registered names whose leading characters correspond to the input sequence of n leading characters, (4) identifying, from the names searched out in the searching step, characters each probable to be input as (n+1)th character and characters improbable to be input as (n+1)th character, and displaying the probable characters and the improbable characters so that the probable characters and the improbable characters are discriminable from each other, and (5) displaying, each time a character is input thereafter, characters each probable to be next input and characters improbable to be next input so that the probable characters and the improbable characters are discriminable from each other.
According to another aspect of the present invention, there is provided a method including forming a table in which (1) each of parent, child and grandchild record is formed by setting characters and bit positions in a one-to-one relationship and by setting a flag at each of the bit positions corresponding to some of the characters each probable to be input in the process of inputting a name, (a) one parent record being formed as a record designating the probability of each of the characters being input as a first character, (b) child records corresponding to the number of the characters being formed, each child record designating the probability of each of the characters being input as a second character subsequent to one of the characters selected as a first character, (c) grandchild records corresponding to the number of possible combinations of first and second characters being formed, each grandchild record designating the probability of each of the characters being input as a third character subsequent to one of the combinations of first and second characters, and in which (2) each of the bits xe2x80x9c1xe2x80x9d or xe2x80x9c0xe2x80x9d of all the grandchild records designates the existence or non-existence in the name list of some registered names whose three leading characters correspond to the predetermined sequence of three characters corresponding to the grandchild record bit.
According to still another aspect of the present invention, when the number of names searched out is reduced to one, the one remaining name is displayed and is input by a predetermined key operation.
These and other advantages and embodiments of the present invention will become apparent with reference to the following detailed specification, claims, and accompanying drawings.